How to recover the MityDSP-L138F u-boot

Description

This procedure will allow you to reprogram the User Boot Loader (UBL) and u-Boot image on a MityDSP-L138/MityARM-1808 module via the serial port AIS bootloader (via UART1, the console port for MityDSP-L138). The AIS bootloader is entered by holding the boot-option button down while resetting (or powering up) a board installed on the PROFIBUS Development kit board.

This procedure should only be needed if a user has corrupted the base of the SPI-NOR FLASH containing the factory installed user-boot-loader and boot image.

This procedure should not be used if a user can boot to the u-Boot prompt. Also, this procedure does not restore kernel/FPGA or root filesystem/NAND data.

At this point, the user-boot-loader and the u-Boot image should be reprogrammed into the SPI-NOR flash. You should be able to launch your terminal program and reset the host board and see the u-Boot prompt as expected.

If you get a message:

Warning - bad CRC, using default environment

in the u-Boot startup, then the u-Boot environment has been reset. You will need to restore any environment settings you had added to your system, and the save the environment using "saveenv".

If you get a message

Error - Checksum on MityDSP-L138 Config Block Checksum Invalid.

You must set the config to FLASH to make permanent

in the u-Boot startup, then the OMAP peripheral configuration block (which selects which emac interface to use, ports to configure, etc.) must be reset and saved. For the industrial I/O board, the default settings should be OK. You can apply the settings be running (and just hitting return for all the prompts):